Yes, the Seattle Mariners. Yes, the team that was last in almost every offensive category in the American League just a few weeks ago.

But the offense is slowly climbing to credibility. And performances like the past two games in Houston will only help. The 13 runs and 18 hits were both season highs. And over the past two games, Seattle hitters have battered the mediocre pitching of the Astros, scoring 23 runs and banging out 29 hits.

A night after hitting four homers in a 10-4 victory, the Mariners totaled eight extra base hits, including five doubles in the sixth inning alone.

Robinson Cano sparked the deluge with a two-out, two-run double off Jarred Cosart, knocking him out of the game. With two strikes on him, Cano reached out and drove a 94 mph fastball above his belt and on the outside corner into the left field corner.

“I said I was going to look for something just middle away but be ready for the one inside,” he said. “Thank God that I was able to hit that pitch down the third-base line because I knew it was high and I was able to keep it fair.”

It was an impossible pitch to hit well and he did it.

But how?

“I don’t know,” said Kyle Seager, who was watching in the on-deck circle. “I wish I did. He’s special. That’s his swing. He stays on the ball, he keeps it down to left. That’s a really hard thing to do. It’s hard to get the ball out of the air to left field for a left-handed hitter, but he does it so well.”

With his first-inning run-scoring single, Cano now is 6 for 14 with two homers, a double and eight RBI in his last three games.

“It was a big at-bat,” Seattle manager Lloyd McClendon said. “He continues to be a clutch hitter for us. He’s driven in some big runs for us. That certainly opened up the floodgates.”

Astros manager Bo Porter turned to lefty reliever Darin Downs to try to keep those floodgates closed and the Mariners’ lead at a respectable 5-1.

He failed, miserably.

In order:

• Seager doubled to right to score Cano.

• Logan Morrison doubled to right center to score Seager.

• Mike Zunino doubled down the left-field line to score Morrison.

• Michael Saunders singled to center to score Zunino.

• Dustin Ackley doubled off the top of the wall in left — missing a homer by inches — to score Saunders.

It all added up to five runs on five hits and a 10-1 deficit.

“This is just one of those nights where the bats came alive and we were swinging well,” McClendon said. “We haven’t had one of those all year.”

According to Stats Inc., the Mariners had never before had six or more consecutive run-scoring hits with two outs in an inning. The barrage of run-scoring hits had the bulk of the 17,504 spectators heading for the exits before the inning came to an end.

Downs finally stopped the hemorrhaging by getting Brad Miller to fly out to the warning track in deep right-center for an out. How bad was it for Downs? He entered the inning with a 2.33 ERA and exited with a 4.12 ERA.

The five doubles in one inning tied a club record. The Mariners hit five doubles in the seventh against the Orioles on July 29, 1991.

All the run support wasn’t needed, but helpful for starter Hisashi Iwakuma, who worked a scoreless sixth inning to end his night.

Iwakuma still didn’t look as dominant as he was a month ago. Lingering neck issues have clearly affected his weekly preparation and his overall command, but he is now feeling 100 percent. He worked through the six innings, giving up one run on seven hits with seven strikeouts and no walks.

“He was OK,” McClendon said. “It wasn’t Kuma’s best outing by no stretch of the imagination but certainly an outing that he can build on.”

After two consecutive subpar outings, Iwakuma was happy with the performance and the progress.

“The last two starts, I felt like I wasn’t contributing and doing my part,” he said through translator Antony Suzuki. “I’m very happy I was able to do my part today. It’s not easy when the team is in a good groove and has good momentum and you aren’t winning.”

Up 10-1 after six innings, the Mariners weren’t satisfied. James Jones, who singled twice early and then had his streak of six consecutive hits stopped by a fly ball in the fourth, tripled to left-center to score Endy Chavez. Pinch-hitter Willie Bloomquist scored Jones with a ground ball to second to make it 12-1.

Reliever Dominic Leone gave a run back in the seventh.

Seager pushed the lead to 13-2, belting his team-high 13th homer.

Blastoff

The Mariners’ moribund offense has sprung to life in Houston:

First 82 games

Past 2 games

Runs per game

4.0

11.5

HR per game

0.8

2.5

Batting average

.242

.349

Slugging pct.

.377

.627

Ryan Divish: 206-464-2373

or rdivish@seattletimes.com

Ryan Divish: 206-464-2373 or rdivish@seattletimes.com; on Twitter: @RyanDivish. Ryan Divish covers the Mariners and offers his perspective all season. He gives his inside look at Major League Baseball and power rankings every Sunday.